Debris cap and method therefor

ABSTRACT

A debris cap apparatus and method, which provides a secure and debris resistant seating of a debris cap within a valve box. The debris cap has two outwardly projecting annuli—a debris seal located near the top of the cap and a retention gasket located distal from the top of the cap. The debris seal blocks debris from entering the valve box when the debris cap is in position. The retention gasket is designed to be pushed down past an inwardly projecting flange within the valve box, to deform as it passes the flange, and then to resume its original shape when past the flange so as to preclude accidental dislodging of the debris cap from the valve box. Where the debris cap is to be used within a pre-existing valve box, an adapter may be provided. It is further preferred to provide a removal tool so as to permit ready removal of the debris cap from the valve box or valve box adapter.

BACKGROUND OF THE INVENTION

[0001] 1. Field of Invention

[0002] This invention relates generally to debris and access caps for access pipes originating at a below-ground shut-off valve and opening at street level, and more specifically, to a debris cap providing both a secure fit and improved debris protection.

[0003] 2. Background of the Invention

[0004] Municipal utilities typically bury their mains under public rights of way, such as streets, at spaced intervals throughout the system. Normally, open shut-off valves are incorporated for the purpose of isolating main breaks so they can be repaired, or so new connections can be established.

[0005] The shut-off valves are frequently buried several feet beneath the street, and access pipes are provided which extend upwardly from the valve to near street level, ending in a valve box. The access pipe provides a passage for a tool which can be manipulated from street level to actuate the valve.

[0006] A cover assembly with a removable lid is usually incorporated in the pavement to cover the opening to the valve box, and possibly also to prevent debris from entering the access pipe. It has been customary to fabricate the cover assembly from cast iron. Cast iron has the advantages of being inexpensive and durable. Iron castings, however, are notorious for dimensional variations from one casting to the next. Consequently, it frequently is the case that there is a poor fit between the cover assembly and valve box—with the result that cover assemblies can become dislodged, creating a potential hazard.

[0007] Nevertheless, cast iron has remained the material of choice because it is strong and capable of withstanding the rigors to which a pavement-mounted assembly is subjected. It has more recently been recognized that quality cover assembly components can be modeled from light-weight synthetic polymeric material. U.S. Pat. No. 4,048,766, granted Sep. 20, 1977, to P. H. Dantzer et al. for “Closure Lid Assembly for Protective Housings” suggests the components be formed by a structural foam molding process. The light weight of the lid in the Dantzer et al. assembly requires that special retaining means and a locking system be provided in the design to prevent the lid from being accidentally dislodged.

[0008] There continues to be a need for an access cover assembly which can be easily molded from polymeric material and which will perform reliably in service—providing both a secure fit (i.e., resisting dislodging), able to be removed in a convenient manner, and also preventing debris from entering the access pipe. There is further a need for a cover assembly having these qualities and which can be retrofitted to existing valve boxes of different sizes. The present invention satisfies these needs and provides other, related, advantages.

SUMMARY OF THE INVENTION

[0009] It is an object of the present invention to provide a light-weight debris cap for an access pipe that provides a secure fit that will resist accidental dislodging.

[0010] It is a further object of the present invention to provide a light-weight debris cap for an access pipe that provides a secure fit that will resist accidental dislodging and that further provides improved debris prevention.

[0011] It is yet a further object of the present invention to provide a light-weight debris cap for an access pipe that may be removed in a convenient manner.

[0012] It is still a further object of the present invention to provide a light-weight debris cap for an access pipe that provides a secure fit that will resist accidental dislodging and that further provides improved debris prevention, and that still further may be retrofitted to different-sized valve boxes.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] In accordance with one embodiment of the present invention, a debris cap apparatus is disclosed. The apparatus comprises, in combination: a debris cap; an annular debris seal positioned about an exterior portion of the debris cap proximate an upper portion of the debris cap and projecting upwardly and outwardly from the debris cap; an annular gasket seal positioned about an exterior portion of the debris cap distal from an upper portion of the debris cap; a valve box; and an inwardly projecting annular flange positioned about an interior portion of the valve box; wherein the inwardly projecting annular flange is positioned within the valve box so that when the debris cap is inserted into the valve box, the annular gasket seal will contact the inwardly projecting annular flange, deform in shape so as to be able to pass by the inwardly projecting annular flange, and return to its original shape below the inwardly projecting annular flange so as to secure the debris cap in position in the valve box.

[0014] In accordance with another embodiment of the present invention, a debris cap apparatus is disclosed. The apparatus comprises, in combination: a debris cap; an annular debris seal positioned about an exterior portion of the debris cap proximate an upper portion of the debris cap and projecting upwardly and outwardly from the debris cap; an annular gasket seal positioned about an exterior portion of the debris cap distal from an upper portion of the debris cap; a valve box adapter having an external configuration dimensioned to conform to an internal configuration of a valve box; and an inwardly projecting annular flange positioned about an interior portion of the valve box adapter; wherein the inwardly projecting annular flange is positioned within the valve box adapter so that when the debris cap is inserted into the valve box adapter, the annular gasket seal will contact the inwardly projecting annular flange, deform in shape so as to be able to pass by the inwardly projecting annular flange, and return to its original shape below the inwardly projecting annular flange so as to secure the debris cap in position in the valve box adapter.

[0015] In accordance with still another embodiment of the present invention, a method for positioning a debris cap within a valve box in a secure and debris resistant manner is disclosed. The method comprises the steps of: providing a debris cap; providing an annular debris seal positioned about an exterior portion of the debris cap proximate an upper portion of the debris cap and projecting upwardly and outwardly from the debris cap; providing an annular gasket seal positioned about an exterior portion of the debris cap distal from an upper portion of the debris cap; providing one of a valve box and a valve box adapter; providing an inwardly projecting annular flange positioned about an interior portion of the one of the valve box and the valve box adapter; wherein the inwardly projecting annular flange is positioned within the one of the valve box and the valve box adapter so that when the debris cap is inserted into the one of the valve box and the valve box adapter, the annular gasket seal will contact the inwardly projecting annular flange, deform in shape so as to be able to pass by the inwardly projecting annular flange, and return to its original shape below the inwardly projecting annular flange so as to secure the debris cap in position in the one of the valve box and the valve box adapter; and inserting the debris cap into the one of the valve box and the valve box adapter until the annular gasket seal passes by the inwardly projecting annular flange and returns to its original shape below the inwardly projecting annular flange.

[0016] The foregoing and other objects, features, and advantages of the invention will be apparent from the following, more particular, description of the preferred embodiments of the invention, as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017]FIG. 1 is a perspective, partially cut-away, view of an embodiment of the debris cap of the present invention in position in a valve box located at street level, and also illustrating the insertion of the removal tool for the debris cap.

[0018]FIG. 2 is a side, cross-sectional view of the debris cap of FIG. 1, and the valve box into which the debris cap is to be inserted.

[0019]FIG. 3 is a side, cross-sectional view of the debris cap of FIG. 1, in position in a valve box.

[0020]FIG. 4 is a side, cross-sectional view of the debris cap of FIG. 1, shown being removed from a valve box using the removal tool shown in FIG. 1.

[0021]FIG. 5 is a top view of the base portion of the debris cap of FIG. 1, showing the compartment into which a wireless transmitter may be placed.

[0022]FIG. 6 is a perspective, exploded view of another embodiment of the debris cap of the present invention, showing a debris cap, adapter, and cylindrical valve box into which the adapter is to be fitted so that the debris cap may be used with an otherwise non-conforming valve box.

[0023]FIG. 7 is a perspective, exploded view of another embodiment of the debris cap of the present invention, showing a debris cap, adapter, and four-sided valve box into which the adapter is to be fitted so that the debris cap may be used with an otherwise non-conforming valve box.

[0024]FIG. 8 is a side of the embodiment of the debris cap of FIG. 7, showing the positioning of the adapter within the valve box and the positioning of the debris cap within the adapter.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Referring first to FIGS. 1-5, a debris cap 10 of the present invention is shown. The debris cap 10, as indicated in FIGS. 1-4, is designed to be fitted within a valve box 12, which valve box 12 is generally positioned in a street 14 or other surface.

[0026] Referring specifically to FIG. 2, the debris cap 10 comprises a lid 14, an annular debris seal 16 positioned about the lid 14 and angled in an upward and outward direction as shown in FIGS. 2-4, a base 18, and an annular retention gasket 20 positioned about the base 18 and angled in an upward and outward direction as shown in FIGS. 2-3.

[0027] The debris cap 10 is preferably made from a thermoplastic material. The debris seal 16 is preferably made from a rubber type of material. The retention gasket 20 is preferably made from a deformable, energy absorbent material, such as Kraton®, so as to prevent rebound and absorb energy. If the retention gasket 20 was made from a non-energy absorbent material, the application of downward force on the debris cap 10—such as by the passage thereover of a vehicle—could cause the retention gasket 20 to “bounce” and spring upward, with the result that the debris cap 10 could be accidentally dislodged from the valve box 12.

[0028] Preferably, as shown in FIGS. 2-4, the debris cap 10 is a multi-piece assembly, with the lid 14 being detachable from the base 18. In this regard, bolts 22 are positioned within posts 24 projecting from the bottom of the lid 14. The bolts 22 enter posts 26 projecting from the top of the base 18, exit recessed openings 28 in the base 18, and are secured with nuts 30. One of the advantages to having the base 18 separable from the lid 14 is to provide a compartment 32 within the base 18, which may be accessed from an upper portion thereof (see FIG. 5) by removing a compartment lid 34 which is retained in position with a screw 36 secured within a post 38, and which may be used to house a wireless transmitter (not shown). Of course, it would be possible to construct a debris cap 10 in which the lid 14 and base 18 comprised a single piece assembly, with the compartment 32 either eliminated or made accessible from the bottom of the base 18.

[0029] Still referring to FIGS. 2-4, the valve box 12 has an inwardly projecting annular flange 40. When the debris cap 10 is inserted into the valve box 12, the retention gasket 20 will compress inwardly so as to pass by the flange 40. When the retention gasket 20 has cleared the flange 40, it will return to its original outwardly projecting shape as shown in FIG. 3. In this position, the retention gasket 20 will strongly retain the debris cap 10 in position in the valve box 12 by resisting efforts to pull it past the flange 40. When the retention gasket 20 is in position below and against the flange 40 as shown in FIG. 3, the debris seal 16 will occupy the opening between the lid 14 and the valve box 12, so as to prevent (or at least minimize) the passage of debris into the valve box 12.

[0030] When the debris cap 10 is in position, it will strongly resist efforts to remove it from the valve box 12. To do so most efficiently and safely, a removal tool 42 is provided, as shown in FIG. 1. The removal tool 42 comprises a handle portion 44 with two hand grips 46 thereon. Projecting downward at right angles from the handle portion 44 are two flat legs 48, each having an angled edge 50, an inwardly recessed area 52 above the angled edge 50, and an outwardly projecting post 54 positioned slightly above the inwardly recessed area 52. A lock bar 56 is slidably positioned on the flat legs 48, with the posts 54 preventing the lock bar 56 from sliding off of the flat legs 48. The purpose of the lock bar 56 is to maintain the proper positioning of the flat legs 48 for removal of the debris cap 10.

[0031] To remove the debris cap 10, the lock bar 56 is slid in an upward direction toward the handle portion 44. The angled edges 50 are then inserted into slots 58 in the lid 14, until the lid 14 is secured within the inwardly recessed areas 52. The lock bar 56 is then slid in a downward direction toward the lid 14. At this point, the debris cap 10 may be removed by the user grasping the hand grips 46 and pulling up, first on one side and then on the other.

[0032] The debris cap 10 as described herein and the valve box 12 are preferably part of a single system, with the valve box 12 having the appropriate internal diameter and flange 40 to mate with the debris cap 10 in a manner that will result in the proper positioning of the debris seal 16 and the retention gasket 20. However, it may be desired to fit a debris cap 10 to an existing valve box, which valve box may already be secured in a street or other location from which it is not readily removable, and which valve box may not be appropriately dimensioned to accept the debris cap 10. Referring now to FIGS. 6-8, a debris cap 10 which may be retrofitted to an existing, non-confirming valve box, is shown.

[0033] Referring first to FIG. 6, the main components of a retrofit system are the debris cap 10, as described above, an existing valve box 120, and an adapter 130. The adapter 130 will have an external diameter conforming to the internal diameter of the particular valve box 120 with which it is to be used. Preferably, adapters 130 will come in different sizes, so as to conform to different valve boxes 120.

[0034] The adapter 130, like the debris cap 10, is preferably made from a thermoplastic material. It has an inwardly projecting annular flange 140, which has the same dimension and performs the same function as the flange 40. To permit fixation of the adapter 130 to the inside of a valve box 120, a plurality of openings 142 are provided in the adapter 130, through which set screws 144 may be inserted and secured to the valve box 120. This will permit a debris cap 10 to be fitted to an existing valve box 120, after fixation of an adapter 130, with the same quality of fit as where a debris cap 10 is fitted to a valve box 12 having a flange 40. This also permits the creation of adapters 130 having different external configurations and sizes to conform to different valve boxes 120, and one or a relatively small number of internal configurations so that a single debris cap 10 could be fitted to multiple different valve boxes 120.

[0035] Referring now to FIGS. 7 and 8, a retrofit system like that shown in FIG. 6 is disclosed, with the difference being that the system of FIGS. 7 and 8 is intended for use with four-sided valve boxes 120′. Thus, the debris cap 10′ is four sided, with a debris seal 16′ and a retention gasket 20′ positioned thereon in the manner and for the purposes described above with respect to the debris cap 10. The adapter 130′, like the adapter 130, will be dimensioned externally to conform to the internal dimensions of the particular valve box 120′ with which it is to be used—with there preferably being adapters 130′ in different sizes, so as to conform to different four-sided valve boxes 120′. The adapter 130′, like the adapter 130, is preferably made from a thermoplastic material. The adapter 130′, like the adapter 130, has an inwardly projecting annular flange 140′, which has the same dimension and performs the same function as the flange 40. To permit fixation of the adapter 130′ to the inside of a valve box 120′, a plurality of openings 142′ are provided in the adapter 130, through which set screws 144′ may be inserted and secured to the valve box 120.

[0036] It should be recognized that it would be possible to have an adapter with a four-sided external configuration like that of adapter 130′ so as to mate with a four-sided valve box like that of valve box 120′, yet with a circular internal configuration like that of adapter 130 so as to accept a circular debris cap like debris cap 10—and vice versa.

[0037] While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention. 

I claim:
 1. A debris cap apparatus comprising, in combination: a debris cap; an annular debris seal positioned about an exterior portion of said debris cap proximate an upper portion of said debris cap and projecting upwardly and outwardly from said debris cap; an annular gasket seal positioned about an exterior portion of said debris cap distal from an upper portion of said debris cap; a valve box; and an inwardly projecting annular flange positioned about an interior portion of said valve box; wherein said inwardly projecting annular flange is positioned within said valve box so that when said debris cap is inserted into said valve box, said annular gasket seal will contact said inwardly projecting annular flange, deform in shape so as to be able to pass by said inwardly projecting annular flange, and return to its original shape below said inwardly projecting annular flange so as to secure said debris cap in position in said valve box.
 2. The debris cap apparatus of claim 1 wherein said annular gasket seal is formed from a deformable and energy absorbent material.
 3. The debris cap apparatus of claim 2 wherein said deformable and energy absorbent material is Kraton®.
 4. The debris cap apparatus of claim 1 further comprising means for removing said debris cap from said valve box.
 5. The debris cap apparatus of claim 4 wherein said debris cap removal means comprises: at least one slot located about an edge portion of said debris cap; and a removal tool dimensioned to be inserted into said at least one slot and then to be agitated so as to impart a substantially upward force so as to cause said annular gasket seal to move in an upward direction past said inwardly projecting annular flange and thereby to permit removal of said debris cap.
 6. The debris cap apparatus of claim 5 wherein said removal tool comprises: a handle portion; two spaced apart flat legs projecting downward at right angles from said handle portion; wherein each said flat leg has on an end portion thereof distal from said handle portion an angled edge dimensioned to be inserted into said slot; wherein each said flat leg further has thereon proximate said angled edge an inwardly recessed area dimensioned to mate with an edge portion of said debris cap when said angled edge is inserted into said slot; wherein each said flat leg further has thereon an outwardly projecting post positioned slightly above said inwardly recessed area; and a lock bar slidably positioned on said flat legs between said outwardly projecting posts and said handle portion.
 7. A debris cap apparatus comprising, in combination: a debris cap; an annular debris seal positioned about an exterior portion of said debris cap proximate an upper portion of said debris cap and projecting upwardly and outwardly from said debris cap; an annular gasket seal positioned about an exterior portion of said debris cap distal from an upper portion of said debris cap; a valve box adapter having an external configuration dimensioned to conform to an internal configuration of a valve box; and an inwardly projecting annular flange positioned about an interior portion of said valve box adapter; wherein said inwardly projecting annular flange is positioned within said valve box adapter so that when said debris cap is inserted into said valve box adapter, said annular gasket seal will contact said inwardly projecting annular flange, deform in shape so as to be able to pass by said inwardly projecting annular flange, and return to its original shape below said inwardly projecting annular flange so as to secure said debris cap in position in said valve box adapter.
 8. The debris cap apparatus of claim 7 wherein said valve box adapter is round.
 9. The debris cap apparatus of claim 8 wherein said valve box adapter is four-sided.
 10. The debris cap apparatus of claim 7 wherein said annular gasket seal is formed from a deformable and energy absorbent material.
 11. The debris cap apparatus of claim 10 wherein said deformable and energy absorbent material is Kraton®.
 12. A method for positioning a debris cap within a valve box in a secure and debris resistant manner comprising the steps of: providing a debris cap; providing an annular debris seal positioned about an exterior portion of said debris cap proximate an upper portion of said debris cap and projecting upwardly and outwardly from said debris cap; providing an annular gasket seal positioned about an exterior portion of said debris cap distal from an upper portion of said debris cap; providing one of a valve box and a valve box adapter; providing an inwardly projecting annular flange positioned about an interior portion of said one of said valve box and said valve box adapter; wherein said inwardly projecting annular flange is positioned within said one of said valve box and said valve box adapter so that when said debris cap is inserted into said one of said valve box and said valve box adapter, said annular gasket seal will contact said inwardly projecting annular flange, deform in shape so as to be able to pass by said inwardly projecting annular flange, and return to its original shape below said inwardly projecting annular flange so as to secure said debris cap in position in said one of said valve box and said valve box adapter; and inserting said debris cap into said one of said valve box and said valve box adapter until said annular gasket seal passes by said inwardly projecting annular flange and returns to its original shape below said inwardly projecting annular flange.
 13. The method of claim 12 wherein said annular gasket seal is formed from a deformable and energy absorbent material.
 14. The method of claim 13 wherein said deformable and energy absorbent material is Kraton®.
 15. The method of claim 12 further comprising the step of providing means for removing said debris cap from said valve box.
 16. The method of claim 15 wherein said step of providing debris cap removal means comprises the steps of: providing at least one slot located about an edge portion of said debris cap; and providing a removal tool dimensioned to be inserted into said at least one slot and then to be agitated so as to impart a substantially upward force so as to cause said annular gasket seal to move in an upward direction past said inwardly projecting annular flange and thereby to permit removal of said debris cap.
 17. The method of claim 16 wherein said removal tool comprises: a handle portion; two spaced apart flat legs projecting downward at right angles from said handle portion; wherein each said flat leg has on an end portion thereof distal from said handle portion an angled edge dimensioned to be inserted into said slot; wherein each said flat leg further has thereon proximate said angled edge an inwardly recessed area dimensioned to mate with an edge portion of said debris cap when said angled edge is inserted into said slot; wherein each said flat leg further has thereon an outwardly projecting post positioned slightly above said inwardly recessed area; and a lock bar slidably positioned on said flat legs between said outwardly projecting posts and said handle portion.
 18. The method of claim 15 further comprising the step of removing said debris cap from said one of said valve box and said valve box adapter with said debris cap removal means.
 19. The method of claim 16 further comprising the step of removing said debris cap from said one of said valve box and said valve box adapter with said debris cap removal means.
 20. The method of claim 17 further comprising the step of removing said debris cap from said one of said valve box and said valve box adapter with said debris cap removal means. 